It is known to incorporate a lift mechanism into a chair to assist an occupant to sit on or get up from the chair. By way of example, U.S. Pat. No. 5,984,411 issued Nov. 16, 1999 to Michael H. Galumbeck discloses a stand chair having an articulated or “split” seat which tilts forward as it is caused to rise up by a single screw drive actuator. As the chair rises, the seat and backrest tip forward and the front portion of the split seat drops away from under the occupant's thighs.
U.S. Pat. No. 7,540,565 issued Jun. 2, 2009 to William D. Lipford shows a similar chair with a split seat which also tips forward as the seat rises. In the Lipford chair, a screw drive causes the seat to rise out of contact with a pair of vertical support members 70.